Astell & Kern Kann Ultra DAP Review

[Heinrich]

They probably better just call it F*ck You (for being so stupid to fall for this kinda BS)

They title "The Ultimate Listening Experience". Hmm, without a hearing device customers are deaf already?

Voted: poor, that needless DAP.

 

[CedarX]

They probably better just call it F*ck You (for being so stupid to fall for this kinda BS)

I believe Fugaku is another name for Mount Fuji in Japanese. I’m sure they want audiophiles to believe, they’ll get “top of the world”, “sacred” audio performances…
I think it’s just meant to be: a “mountain of money the size of Mount Fuji”…

 

[M.C. Logan]

I wonder why this kind of product still exists.

Because:
A) Having a cable stuck in your phone is inconvenient.
B) Having a cable stuck in your phone means it can't be charging.
C) You want more and more easily managed storage than phones come with.
D) Listening to music won't deplete your phone battery.
E) It should be possible to build better.
F) Separate tools for separate jobs.

Many reasons. A&K are overpriced, underperforming and with poor industrial design though.

 

[Tatr76]

Will stick with my old re purposed s10 phone with 1tb sd card and neutron player installed. Dongles are cheap if not want to use phone jack and ios fast and can do so much more.

 

[antcollinet]

Now I just put mysmartphone in 'do not disturb' mode

Exactly. In fact I don't have intrusive notifications at any time. The phone is to do what I want it to do when I want it to - not the other way around.

 

[AaronJ]

Company is about 12 years old. With the sluggish UI it seems that not much innovation has been done since then. The price (mostly the paperweight casework) is the product, and in that regard it is performant. Golfing panther.

 

[AaronJ]

Because:
A) Having a cable stuck in your phone is inconvenient.
B) Having a cable stuck in your phone means it can't be charging.
C) You want more and more easily managed storage than phones come with.
D) Listening to music won't deplete your phone battery.
E) It should be possible to build better.
F) Separate tools for separate jobs.

Many reasons. A&K are overpriced, underperforming and with poor industrial design though.

I can't say I agree with any of these.

How is having a cable stuck in your phone any less convenient than having a cable stuck in a second device? Is battery life of phones still an issue in 2025? I have never known a single person to complain that they have to stop listening to music to charge their phone (I'm sure there are some who will voice that opinion on this forum though). Streaming services allow many GB of temporary storage on a phone when the streaming service is not available, like on an airplane. I can't imagine having enough music that I'd actually want to listen to filling up 2TB. Considering the performance of modern dongles if one insists on using wired headphones on the go, there is no reason for DAP's to even exist, let alone be expensive.

 

[MonkeyKing]

Because:
A) Having a cable stuck in your phone is inconvenient.
B) Having a cable stuck in your phone means it can't be charging.
C) You want more and more easily managed storage than phones come with.
D) Listening to music won't deplete your phone battery.
E) It should be possible to build better.
F) Separate tools for separate jobs.

Many reasons. A&K are overpriced, underperforming and with poor industrial design though.

Just to test that theory I bought a HiBy to see how it goes...

 

[CedarX]

How is having a cable stuck in your phone any less convenient than having a cable stuck in a second device?

I have this second device in my pocket, which let me use my phone with no cable.

Is battery life of phones still an issue in 2025?

Absolutely yes... Especially with my aging phone.

I have never known a single person to complain that they have to stop listening to music to charge their phone (I'm sure there are some who will voice that opinion on this forum though).

I do complain about this.

Streaming services allow many GB of temporary storage on a phone when the streaming service is not available, like on an airplane.

It assumes GB of temporary storage available on the phone. Definitely not the case on my iPhone. Also, I'm not good at planning what I'm going to listen to.

I can't imagine having enough music that I'd actually want to listen to filling up 2TB.

I was just reading a post on Head-Fi about this guy buying a 2TB sd for his 70,000+ tracks music library.

Considering the performance of modern dongles if one insists on using wired headphones on the go, there is no reason for DAP's to even exist

There are entire threads dedicated to dongles, and not every post is about how great the performances are. There are reasons for DAPs to exist, even if they are not good reasons for you.

I can't say I agree with any of these.

I can say I disagree with almost all of this.

let alone be expensive

This, I agree...

 

[Somafunk]

Just to test that theory I bought a HiBy to see how it goes...

Good luck, and welcome to the Hiby family

What model did you purchase?

 

[JDS]

This is a review and detailed measurements of the Astell&Kern Kann Ultra DAP. It is on kind loan from a member and is on sale for US $1,499.
View attachment 444562
Forget any notion you have of a smartphone. This thing looks like one but is far, far heavier and thicker. Machining has left sharp corners which are unkind on fingers. The rotary volume control is slow and the display for it does not keep up.

On positive front it has wifi streaming including support for Roon! Didn't see that coming from a portable player. I tested both Roon streaming and playback using its USB-C cable. Yes I know, many will use an SD card with it but performance should be the same.

There are a set of balanced and unbalanced connections for Line and Headphone out:
View attachment 444563
As you see, labels are hard to read. The heavy weight of the unit comes in handy when using it on the desktop.

Astell&Kern Kann Ultra Measurements
Let's start with line out at max volume using balanced output:
View attachment 444564
This is impressively good for a DAP! Distortion is inaudible and noise floor is good. Both suffer though with unbalanced output:
View attachment 444565

Measuring noise by itself, it turns in very nice numbers, almost approaching dedicated desktop products:
View attachment 444566

There are selectable filters; I chose the fast linear which resulted in nice frequency response:
View attachment 444567
Linearity is as it should be:
View attachment 444568

Story becomes less good when we look at IMD distortion:
View attachment 444569
Jitter seems unsightly, though inaudible:
View attachment 444570

Multitone shows raised noise floor at lower frequencies:
View attachment 444571

That is a clue to issues there when we run distortion vs frequency:
View attachment 444572

To save my sanity, I only tested balanced headphone out, starting with 300 ohm load:
View attachment 444573
While we have plenty of power in max "Super" setting, there is much elevated noise. Even more strange is very limited power at 32 ohm:
View attachment 444574

We can see the strangeness in full exposition when we sweep impedances using high gain:
View attachment 444575

This is not how it should be for a device that is very focused on headphone output.

Conclusions
The Kann Ultra starts strong, turning in very good noise and distortion numbers as a DAC using balanced output. From there though, cracks in the foundation is seen, culminating in a headphone stage that is very poorly designed when it comes to gain management and low impedance loads. It should however be good if you use high impedance headphones.

Overall, this seems like partial improvement. And partial improvement is not what want to see in a device that costs $1,500.

I can't recommend the Astell & Kern Kann Ultra DAP.

------------
As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

Even if this $1500 device didn't have performance issues, I confess I have trouble understanding the point in 2025. I run Roon ARC on my iPhone for music when out and about. 90% of the time that means noisy environments where any theoretical improvement in fidelity would be inaudible. And with the iPhone/Roon ARC setup, if I have either cell coverage or WiFI, I can access my entire home library. What would I gain if I switched to this?

 

[JDS]

Those IEM's are truly remarkable, aren't they? -I absolutely love mine.

Regardless of their audiophile cred, they pack a ton of functionality into those tiny things. Just wish they stayed in my ears better.

 

[xanalog]

Thank you for the review, @amirm, and thanks go out to @HELIAS for sharing.

...And given that almost everyone who wants a portable player will already have a smart phone, I really struggle to find a reason for this things existence.

I've had many DigitalMediaPlayers and the last one was a xDuoo X20 purchased 6 years ago. Now a discontinued product, running on ES9018K2M. It is my main music player feeding our cars' audio systems when we are 'mobile'. I carry three 256MB microSD cards that are a part of my digital music library.
As I was preparing this reply - for those who see a Digital(/Portable Media(/Music) Players (DMP/PMP) as being unnecessary in our 21st Century digital/connected world - I ran across the xDuoo's X5 player for $200 at their website and ordered one as a replacement for my 6 yr. old X20. Although, my current xDuoo X20 has served me well; while never needing resets, reboots, and/or crashes.

The newer xDuoo X5 can handle 1TB microSD cards, which makes me very .

I will probably contact @amirm, to see if he'd be interested to test/review my new/old xDuoo music players.

 

[Bob101]

Exactly. In fact I don't have intrusive notifications at any time. The phone is to do what I want it to do when I want it to - not the other way around.

That's why Android.

 

[antcollinet]

That's why Android.

My phone is an iphone, thought I'd be pretty confident you can achieve the same with Android.

 

[kyuu]

My phone is an iphone, thought I'd be pretty confident you can achieve the same with Android.

Sure. The problem with using DND is, well, you don't get notifications. My notifications are pared down to the ones I want, and I generally don't want to miss them. When I'm on-call for work, I really cannot miss them. The result is that I really need something that's not my phone for listening to music. I would settle for at least being able to disable the audio ducking feature, but that appears to be something that developers of mobile phone OSes have decided is an obviously desirable thing that no one would ever find unnecessary and annoying.

 

[antcollinet]

My notifications are pared down to the ones I want, and I generally don't want to miss them.

The ones I don't want to miss come through as a silent (as far as the phone is concerned) buzz on my garmin watch.

 

[Somafunk]

Even if this $1500 device didn't have performance issues, I confess I have trouble understanding the point in 2025. I run Roon ARC on my iPhone for music when out and about. 90% of the time that means noisy environments where any theoretical improvement in fidelity would be inaudible. And with the iPhone/Roon ARC setup, if I have either cell coverage or WiFI, I can access my entire home library. What would I gain if I switched to this?

Not much to really gain except it’s sometimes nice to have things that are complementary.

Why bother with an expensive streamer/playback system when you could easily connect a Hiby R3 ii dap @ £130 to a pair of well measuring £300 active speakers and have a perfect system (within reason), or why bother with a streamer at all if you have a pc/Mac that you can connect

 

[Somafunk]

As I was preparing this reply - for those who see a Digital(/Portable Media(/Music) Players (DMP/PMP) as being unnecessary in our 21st Century digital/connected world - I ran across the xDuoo's X5 player for $200 at their website and ordered one as a replacement for my 6 yr. old X20. Although, my current xDuoo X20 has served me well; while never needing resets, reboots, and/or crashes.

You may want to hold off on that purchase as the reviews of the xduoo are rather bad due to software implementation, screen lag, noticeable hissing and popping under playback, strange button controls and quite a few other issues.

Have a look at the YouTube Reviews, not good at all for the device

 

[monkeyboy]

I prefer a DAP, the iBasso DX180 looks pretty interesting, I'd love to see it tested. But I won't buy it until I know the performance...so a bit of a chicken egg thing with regard to sending it in for testing.

An LG phone was a good choice at the time, but now phones don't have headphone jacks, and I think using a dongle will put a lot of stress on the USB connection...but I may end up going that route when the battery in my LG G8 dies...it's a 50:50 chance you break it tying to replace the battery...

I recently replaced the battery and installed Rockbox on an old iPod, it's a great little device! Perfect for just music, but you can't download podcast directly to the device so it's a bit of hassle to manage podcast episodes...